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151.
INTRODUCTION: The aim of this study was to examine usefulness of oral glucose tolerance test (OGTT) in clinical evaluation of different glucose metabolism disturbances in subjects with at least one risk factor of type 2 diabetes. We compared the effectiveness of non-pharmacological and pharmacological prevention and treatment regiments on metabolic control in these individuals. MATERIAL AND METHODS: The study involved 130 patients, with the following characteristics: age between 18 to 76 years, mean body mass index (BMI) - 31.82 +/- 7.24 kg/m(2), and presence of at least one of the risk factor of type 2 diabetes. Glucose metabolism disturbances were diagnosed according to World Health Organization (WHO) criteria. Non-pharmacological regiments were applied for 3 months for patients with impaired glucose tolerance (IGT) and type 2 diabetes. Patients, whose still met criteria for type 2 diabetes during OGTT after non-pharmacological treatment were scheduled for pharmacological interventions. These patients were assigned at random to two groups, that were treated with either metformin or acarbose. The measurements of total cholesterol (TC), HDL-cholesterol , LDL-cholesterol, trigliceryde (TG), glucose, HbA(1c) and/or OGGT were performed during each visit. We also assessed risk factors for type 2 diabetes in these subjects. RESULTS: The prevalence of abnormal glucose tolerance in subjects with at least one of the risk factor of diabetes type 2 was near 40%. OGTT in these subjects increased the possibility of diagnosis diabetes type 2 and IGT. Hypertension (81%), hypercholesterolemia (71.4%), hypertriglicerydemia (71.4%) and obesity (66.7%) were the most frequent risk factors observed. There were no differences in biochemical measurements between these groups of patients. CONCLUSIONS: Individuals with at least one risk factor of type 2 diabetes should have screening test to diagnose glucose intolerance. Both non-pharmacological and pharmacological intervention was effective in normalization of glucose OGTT in patients with diabetes type 2 and IGT in newly diagnosed with disease patients.  相似文献   
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The number of malaria parasite clones per infection-multiplicity of parasite clones-is affected by the transmission intensity, multiplicity increases with increasing transmission. This affects the frequency of parasites' sexual recombination and, if several mutations in different genes are involved, can break down drug resistant genotypes. Therefore, the effects of malaria transmission intensity on the spread of drug resistance could vary depending on the number of genes involved. Here we show that, compared to low transmission, intermediate-high transmission is associated with a 20-100-fold lower risk for the mutations linked to chloroquine resistance and a 6-17 times higher risk for those linked to sulphadoxine-pyrimethamine resistance. This is consistent with the hypothesis of a multigenic basis for chloroquine resistance and a monogenic basis for that of sulphadoxine-pyrimethamine. Reducing transmission intensity could slow the spread of resistance. However, a reduction below a critical threshold (e.g. when parasite prevalence in children 2-9 years old is around 60-80%) could, paradoxically, accelerate the spread of resistance to chloroquine and possibly to other drug combinations whose basis is multigenic. Our findings have important implications for malaria control because increasing drug resistance has a substantial impact on mortality.  相似文献   
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Recent developments in infrared laser technology have enabled the design of a compact instrumentation for two-photon excitation microparticle fluorometry (TPX). The microparticles can be used in immunoassays as the antibody-coated solid phase to capture an antigen and then detect it with a fluorescently labeled tracer antibody. Unlike most other methods, TPX technology allows low-volume, homogeneous immunoassays with real-time measurements of assay particles in the presence of a moderate excess of fluorescent tracer. In this study, the TPX assay system was used for the reagent characterization and the measurement of C-reactive protein (CRP) in diluted plasma samples, targeting the assay range useful in infectious disease diagnosis. The pentameric structure of the CRP permitted the optimization of an assay with the lowest detectable concentration of 1 microg/L (7.5 pM) by using a single monoclonal antibody both for capture and as the tracer. With a 1:200 predilution of samples, the measurement range of the assay was 1-150 mg/L, but an additional 1:10 dilution was required for higher concentrations. The TPX method showed a good correlation with the reference result obtained in a routine hospital laboratory, demonstrating the feasibility of the technology for immunodiagnostic applications.  相似文献   
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Physical phantom models have conventionally been used to determine the accuracy and precision of radiostereometric analysis (RSA) in various orthopaedic applications. Using a phantom model of a fracture of the distal radius it has previously been shown that RSA is a highly accurate and precise method for measuring both translation and rotation in three-dimensions (3-D). The main shortcoming of a physical phantom model is its inability to mimic complex 3-D motion. The goal of this study was to create a realistic computer model for preoperative planning of RSA studies and to test the accuracy of RSA in measuring complex movements in fractures of the distal radius using this new model. The 3-D computer model was created from a set of tomographic scans. The simulation of the radiographic imaging was performed using ray-tracing software (POV-Ray). RSA measurements were performed according to standard protocol. Using a two-part fracture model (AO/ASIF type A2), it was found that for simple movements in one axis, translations in the range of 25microm-2mm could be measured with an accuracy of +/-2microm. Rotations ranging from 16 degrees to 2 degrees could be measured with an accuracy of +/-0.015 degrees . Using a three-part fracture model the corresponding values of accuracy were found to be +/-4microm and +/-0.031 degrees for translation and rotation, respectively. For complex 3-D motion in a three-part fracture model (AO/ASIF type C1) the accuracy was +/-6microm for translation and +/-0.120 degrees for rotation. The use of 3-D computer modelling can provide a method for preoperative planning of RSA studies in complex fractures of the distal radius and in other clinical situations in which the RSA method is applicable.  相似文献   
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INTRODUCTION: Apoptosis plays a pivotal role in the regulation of immune mechanisms in the pathogenesis of autoimmune thyroid diseases (AITD). The prevalence of AITD increases with age. Purpose to compare soluble Fas, FasL and Bcl-2 in Graves disease (GD) and Hashimoto thyroiditis (HT) in relation to the age of the studied patients. MATERIAL AND METHODS: 3 groups of subjects: 1/25 patients with GD in euthyreosis on methimazol 2/27 patients with ChH in euthyreosis on levothyroxine. 3/12 healthy volunteers age and sex-matched to group 1-2. The serum levels of Fas, FasL and Bcl-2 were determined by the ELISA kit. RESULTS: We found positive correlations between sFas and age in GD patients (r = 0.35; p < 0.05). In GD patients we found a negative correlation between sFasL and age in all studied patients with AITD (r = -0.34; p < 0.01). We also found a negative correlation between sBcl-2 and age in HT patients (r = -0.42; p < 0.05). CONCLUSIONS: Fas/FasL and Bcl-2 signaling pathways seem to be age-related and may explain, at least in part, milder course of Graves disease in elderly patients and increased prevalence of Hashimoto disease in this group of subjects.  相似文献   
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Choisya ternata Kunth (Rutaceae) is native to North America where it is popularly known as “Mexican orange”. In this study, the anti-inflammatory effects of the essential oil (EO) obtained from the leaves of C. ternata, one of its minor components (ternanthranin—ISOAN) and its two synthetic analogues (methyl and propyl N-methylanthranilate – MAN and PAN) were evaluated. Mice pretreated with the EO (EO) obtained from C. ternata leaves (3–100 mg/kg, p.o.), ISOAN, MAN or PAN (1–30 mg/kg, p.o.) and the reference drugs, morphine (1 mg/kg, p.o.) and acetylsalicylic acid (ASA, 100 mg/kg, p.o.), were evaluated in inflammation models such as formalin and subcutaneous air pouch models, with measurement of cell migration, exudate volume, protein extravasation, nitric oxide and pro-inflammatory cytokines. The EO from C. ternata significantly inhibited the time that the animals spent licking the formalin-injected paw in the second phase of the model at their higher doses (30 and 100 mg/kg, respectively). An inhibition of the inflammatory reaction induced after subcutaneous carrageenan injection into air pouch was also observed. In this model, the EO significantly reduced cell migration, exudate volume, protein extravased, and the increase in levels of inflammatory mediators (nitric oxide, TNF-α and IL-1β). ISOAN, MAN and PAN behaved in the same fashion at much smaller doses. Also, these molecules were able to show significant effects in the reduction of paw edema (at all tested doses) when the phlogistic agent was carrageenan, bradykinin, 5-HT, PGE2, C48/80 or 12-O-tetradecanoylphorbol-acetate (TPA). None of the tested doses had any effect in reducing histamine-induced edema. Our results indicate that the EO from C. ternata and anthranilate derivatives demonstrates an anti-inflammatory effect.  相似文献   
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